… But some Israeli commanders, who agreed to share their assessments of the Syria conflict on the condition they not be identified, went as far as saying that the American actions in Syria and Iraq, where U.S.-backed Iraqi forces recently liberated the city of Mosul, could be turning ISIS and its affiliates elsewhere in the region into an even bigger threat to the West….

… In eastern Syria, where ISIS is believed to be strongest, “the population is relatively favorable to the Islamic cause—the tribes and so forth,” he added..

Yavne, the (IDF) brigadier general, similarly described the Iranian influence as significantly more worrisome than ISIS or other Sunni Muslim terror groups:

“If I can be frank, the radical axis headed by Iran is more risky than the global jihad one,” said Yavne. “It is much more knowledgeable, stronger, with a bigger arsenal.”

As far as these Israeli officers are concerned, the ideal strategy is to sit back and let both types of groups duke it out—and work to contain the conflict rather than trying to end it with military force. As the IDF intelligence officer put it, “the battle for deterrence is easier than the battle for influence.”

But does that mean the United States and its allies should simply allow ISIS to retain its so-called caliphate in parts of eastern Syria and eastern Iraq?